Body-Size Dependent Anti-Predator Mechanisms of the American Lobster

Like many lobsters and crayfish, the American lobster Homarus americanus exhibits an ontogenetic shift from a strong, apparently predator reinforced association with sheltering habitats early in life to an increasingly wide ranging existence as it grows. At least in part, this shift may be related to a change in behavioral responses to predators, but neither the sensory capabilities nor the size-specific responses of lobsters to predators are well studied. I conducted laboratory experiments to determine the response of early benthic phase lobsters (ca. 5 to 40 mm carapace length) to the physical and chemical presence of fish predator